Stitch-fobming mechanism fob



mirino STATES PATENT ernten OSCAR L. LAWSON. 0F LYNN, MASSACHUSETTS, ASSIGNOR OF ONE-HALF TO CARL ANDERSON, OF LOWELL, MASSACHUSETTS.

STITCH-FORMING MECHANISM FOR SHOE-SEWING IVIACHINES.

Patented Aug. 15, 1916.

Original application filed May 29. 1914. Serial-No. 841.752. Divided and this application filed March 25, 1915. Serial No. 17,046.

To il whom it muy wom-vivi.'

Be it known that l. (lst-an L. L.\wsoN, a subjectfof'the King ot' Sweden. residing at L vnn. county ot Essex` State of Massachusetts` have invented a certain new and useful Improvement in Stitch-Forming Mechanism for- Shoe-Sewing ll'lacliines, of which the. following is a specification. reference being had therein to thiI accompanying drawings.

This is a division of inyprior application Serial Numbei 841,752. filed ,May 25), 191i. for Lock stitch sewingr machine.

This invention relates to sewing machines for leather work. and has particular reference to the. loopers for a sewing machine of the character described'.

My improvements are designed with special reference toproviding a sewingr machine which will be of low cost and elt'ective for use iy'cobblers as well as for the general purposes to which leather sewing machines are put.

The particular object of my invention is to provide improved mechanism for laying the thread in the hook of the needle.

The mechanism shown and described herein may be operated by a single cam but gives to the thread the requisite motions and therefore results in greatly sin'iplifyinpj` the construction of the machine in which itis embodied. making it-possilile to .produce an etlicient machine at a vcry smallexpeiise.

Tln` invention will lie fully understood b v reference. to the following specification. taken in connection with the accoinpairviirl drawings, and the. novel` .features thcreot` are pointed out and distinctly defined in the claims at the close of this specification.

In the accompanying drawings. Figure 1 is a detail side elevation of the stitch forminer mechanism and the mechanism for layiner the thread in the hook of the needle together with the cam and the operating mechanism therefor. Figs. Q and 3 are detail front elevations of the mechanism for layingr the thread in the hook of the needle. said two figures illustrating; the parts in dilierl ent positions. Fig. 4 is an elevation look` ingi from the left of Fig. l2. Fig. 5 is a plan view looking down from line 5 5 in FigA 3.

Similar reference characters indicate the same or similar parts in all the views.

In the drawings, at 30 is shown the work support; at 31 the hook needle; at 33 is shown the segment to which the. needle is secured. The `awl is'shown at and it is to be understood that the lnacliine is of the type known as a-wl-feed, that is.; by snitable mechanism not necessary to describe or illustrate in detail, the awl passes through 60 a slot in the work support and shifted when in upper position so as to feed the work along. These parts are. in general oldand well known and are further described in my prior application vto which reference has heretofore been made.

The means for laying the thread in the.' hook of the needle when the latter is in the lower position, that is,the position shown4 in Fig. 4. consists in a tubular guidevor looperiGS and a hook 69, carriedrespectively1 by the arms or levers '70 and'l, pivoted'at v7'2 to a block 73 pivotally mounted or hung upon a pin 71 carried'by an arm 75. which is pivotally supported at 7G by the frame of 75 the machine. The pivotal connection 72 between the levers and the block 73 is such that said levers are held against the basel of the block so that while they may oscillate relatively to each other on the pivot 72 they l80 will follow all the swinging mot-ions of the block 73.

A lever i' pivotally supported at 78 and pivotally connected at79 to the block 73 has a roll which is eiigaged by a suitably 85 formed cam groove in the side of the disk 5S. As the lever 7T is moved up and down liv the cani its own pivotal connection. and thil pivotal connection with the block 73 and the support of the latter by the swingin;r arm 75 result in the guide or looper G8 and hook G9 having the .following motions :hlt being understood of course that .the thread which is to be engaged b v the hook needle is permanently in the tubular then as the needle passes down through the slot of the work support the said guide or` looper and hook move upwardly. At the same time the hook shifts across the top of the guide and moves laterally to the position shown inFig. 2, so as to stretch a por# 10.c

tion of the thread substantially horizontally behind the needle, the .guide and hook then shifting slightly forward to lay the thread in the. needle hook. 'Y Y I will now describe the mechanism vwhich ca ,uses'the two levers to swing( relatively to each other from the position'shown in F ig.

lower end's'of the levers 70 and 71 are formed with extensions or-'cam lugs 8l, 82 respectively, said lugs extending down'V between twoixed guide pins 83 projecting from ,a

" frame bracket 84., The-sides of the lug 81 are preferably straightand parallel;- the lug being slightly inclined to one side the lug 82 having its sides curved and inclined more`- than the lug 8l and in a direction opposite the inclination of the lug 81. This is in 0r- `der to impart considerably more lateral movement to the hook A69 than to the guide 68. Asthe block .w73 is shifted up and down, the lugs 81 and 82 slide between the fixed pins 83 projecting from the frame bracket 84, and cause the guide 68 and hook 69 to followthe paths described, or reach the positions indicated in the drawings.

Assuming that the guide and hook occupy the position shown in Fig. l and the sewing "operationthen proceeding,'t he levers begin 'torise with the guide and hook both shift- 'ing to the rear as they move upwardly. The hook then moves across the top of the guide toward the position shown in Fig. 3, then continues to the position shown in Fig. 2. Just before reaching the last mentioned p0- sition, the swing 'of the block Z3 is such that the guide and 'hook move forwardly and lay the thread in the hoolcof the needle. The needle then begins to rise and the guide and hook retreat toward and to the position shown in Fig. l. 1` Y Frein the foregoing it will be seen that the oscillating or opening .and shutting move ment'of the guide or looper G8 and hook 69 aswell the swinging movement of the said members about the pivots/74 and 76 wholly by the movements of l n on the'disk 58, and that therethe :me

median-issn is provided for laying the thread .in the nook ofthe needle.

What I elaimis: l Y

l. A looper inechanismvfor'a hook needle sewing machine comprising a pivotally supported block, a pair of arms pivbt'ally con'- nected to -said block, one arm having a thread guide, and the other having a hook, means for raising andA lowering the block and swinging it to shift the guide and hook l to and'from juxtaposition to the path of the needle hook to vpresent the thread in position to be engaged by the needle hook, and

a simple and inexpensive'but effective' means for swinging said arms on their pivots as they rise and descend with the I v. ported block, a pair of arms pivotally con- 1.'to'the position shown in Fig. Zz-The z nected to' saidblock, one arm having a thread guide, vandthe other havinga hook, means for raising and lowering the block and swinging'it to shift the guide and hook to and from juxtaposition to theA path of the v needle hook, said arms having cam portions, and fixed members between which said cam portions slide, whereby the thread is presented to a position to be engaged by; the

hook of the needle andis then spread tov draw out the thread for vformation cfa loop by movement of the needle.

3. A looper mechanism for a vhook needle sewing machine comprising a piiotally supported block, a pair of' arms pivotally con' nected to saidjblock, one arm having a thread guide, andthe other having a hook, means Vfor raisin r and lowering the block and swinging il, @l shiftthe guide and hook to and from a ,zgsition in 'a plane in juxtaposition to thevpath of the needle hook tov present the thread to be engaged by the needle hook, said arms havingdiverg'ing lower ends, andfixed pins between. which said ends slide, to spread-apart Athe guide and Ahook and draw out the't'hread for formation of a loop 'after it is engaged by the needle hook..

- 4. A looper mechanism for a hook needle and swinging it vto shift the guide and hook sewing'machine comprising a pivotally supto and from a position in a plane in juxta- 1 position to the path of the needle hook to4 present the thread for engagement by the needle hook, said 'arms having diverging lower ends, and fixed pins between which said ends slide, the lower end of the arm having the hook Vbeing curved, the 'lower endof the other armbeing substantiallystraight, to spread apart the guide and hook and draw out the thread for formation of a loop by the hook when the blockv moves upward 'i and then to move the guide and hook again toward each other when the block moves l downward.

In testimony whereof` I affix myv signature, in presence of two witnesses.

' OSCAR L. LAWSON. lVitnesses:

GEORGE P. Dina, ALICE H. MonmsoN. 

